Under the deal with Britain, China, France, Germany, Russia and the United States, Iran agreed to restrict its nuclear program in return for the removal of sanctions that have crippled its economy.

Despite that, big banks have continued to stay away for fear of falling foul of remaining U.S. sanctions - something that has hampered Iran’s efforts to rebuild foreign trade and lure investment.

Adding to those concerns, U.S. President Donald Trump told the Europeans on Jan. 12 they must agree to “fix the terrible flaws of the Iran nuclear deal” or he would re-impose the sanctions Washington lifted as part of that pact.

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But even if Trump relents and issues fresh “waivers” to continue suspending those sanctions, the existing situation is unacceptable for Iran, Deputy Foreign Minister Abbas Araqchi said.

“The deal would not survive this way even if the ultimatum is passed and waivers are extended,” Araqchi, Iran’s lead nuclear negotiator, said in a speech at the Chatham House think tank in London.

“If the same policy of confusion and uncertainties about the JCPOA (Joint Comprehensive Plan of Action) continues, if companies and banks are not working with Iran, we cannot remain in a deal that has no benefit for us,” Araqchi said. “That’s a fact.”

Trump sees three defects in the deal: its failure to address Iran’s ballistic missile program; the terms under which international inspectors can visit suspect Iranian nuclear sites; and “sunset” clauses under which limits on the Iranian nuclear program start to expire after 10 years.

FILE PHOTO: A display featuring missiles and a portrait of Iran's Supreme Leader Ayatollah Ali Khamenei is seen at Baharestan Square in Tehran, Iran September 27, 2017. Picture taken September 27, 2017. Nazanin Tabatabaee Yazdi/TIMA via REUTERS ATTENTION EDITORS - THIS IMAGE WAS PROVIDED BY A THIRD PARTY/File Photo

He wants all three strengthened if the United States is to stay in the JCPOA.

Araqchi said Trump’s interpretation of the sunset clauses was wrong.

“There is no sunset clause in the JCPOA. Although the U.S. administration and Trump are talking about sunset clause and that JCPOA is just for 10 years, that is not true,” he said.

“Iran’s commitment in the JCPOA not to go for the nuclear weapons is permanent.”

He also reiterated Iran’s position that the JCPOA was a non-proliferation treaty and could not be linked to any other issue.

If the nuclear deal is linked to Iran’s ballistic missile program or its regional activities, world powers “not only will lose the JCPOA, but will make other issues more complicated and more difficult to resolve,” he said.

“If we lose the JCPOA, we will face another nuclear crisis,” Araqchi said.

“For the Europeans or the world community, when we talk about maintaining the JCPOA and saving it, it’s not a choice between the Iranian or the U.S. market, it’s not a choice for economic cooperation: it’s a choice between having security or insecurity,” he said.